Attorneys for the District's Public Defender Service asked the D.C. Court of Appeals yesterday to declare the city's controversial preventive detention law unconstitutional on grounds that it amounts to punishment without a full trial.

The argument was made in the first major court challenge to the application of the 10-yar-old statute in a criminal case here. The statute allows a criminal suspect to be held without bond pending trial if he is perceived to be a danger to the community.

All nine judges of the D.C. appellate court, rather than the usual three-judge panel, heard the arguments. In addition to the argument on the law's constitutionality, the panel also heard argument that the preventive detention hearings should be open to the public and press, instead of closed, as D.C. Superior Court judges have ordered in two recent cases.

Under the statute, a criminal defendant can be held without bond for up to 60 days if he fits certain specific criteria, such as having been convicted of certain violent crimes in the past or is currently being charged with a crime in which the evidence is unusually strong.

The public defender service attorneys said the act is unconsitutional because its only purpose seems to be "to protect the community from anticipated criminal acts . . . [It] is punishment for the propensity to do evil."

Even if the act is constitutional, attorney James McComas further argued, it should only be applied in a hearing in which strict rules of due process are followed. For example, McComas said, the defendant should be given the right to confront his accusers, and be allowed to call the alleged victim as a witness.

Assistant U.S. Attorney Michael Farrell argued, however, that such rules would turn the pretrial detention hearing into a full-scale trial that was not anticipated by Congress when it passed the law.

He said the application of the strict rules requested by the Public Defender Service "would so totally encumber the system as to destroy [the law's] utility."

In addition, he added, crime victims should not be forced to the "humiliating ordeal" of having to testify about their case one additional time so soon after the defendant is arrested.

Attorney Kevin Baine, meanwhile, argued for The Washington Post that the preventive detention hearings should be held in public, decrying the closure of the courtroom in such hearings recently by D.C. Superior Court Judges. The post has entered the case as a friend of the court, hoping to have the hearings opened in all instances.

Baine said the preventive detention case was important to the public since "vital issues were debated and decided in the proceeding that was secret."

The arguments were made in a case involving Marvin L. Edwards, a 17-year-old who has reportedly admitted his involvement in a rape and 16 other violent crimes.

D.C. Superior Court Judge Shellie F. Bowers refused to hold Edwards under preventive detention in the rape case last month. He made that ruling behind closed doors after defense attorneys said Edwards might have difficulty receiving a fair trial if the hearing was held publicly.

A week later, however, D.C. Superior Court Judge David Norman ordered Edwards held under preventive detention in another sexual assault case. A large portion of that hearing was also held behind closed doors.